Bearing metal alloy



R0 Drawing.

To all whom it may concern:

Be' it known that we, KARL Miiunu and WILHELM SANDER, citizens of the German Republic, and residing at Essen, Germany, have invented a new and useful Improvement in Bearing Metal Alloys; and we do hereby declare the following to be a full, clear, and exact description of the same.

This invention relates to bearing metal alloys with the characteristic feature of a high (75 to 80 per cent) lead content.

Bearing metalsof this type have latterly been frequently and largely employed in practice. Alloys of this kind have approximately the following composition: about 80 per cent of lead, about 10 to 15 per (ent of antimony, about 5 to 10 per cent of tin, together with small intentional additions of co per.

evertheless up to the present the field of technical ap lication of such bearing metals of high lea content has been limited.

In the case of heavy loads a bearing metal with high tin content hadalw ays to be used.

The alloys of the above composition high in lead have mostly an insuflicient degree of hardness, usually below or approximately 20 Brinell. Moreover, when submitted to heavy strains and especially when the lubrication fails these bearin crumble (or scale), individual small parts of the bearing becoming detached, a disadvantage which at once produces hot running and thus causes serious interference with the working of the machine. This tendency to crumble is especially dangerous when the direction of rotation is suddenly changed, as often ha pens in railway shunting.

Accor ing to our invention these drawbacks are avoided and the properties of such bearing metals as mentioned above, consisting mainly of lead, and containing antimonyand tin are considerably improved by a small percenta say about 0.5 or cent of phosphorus, w ich is added to t e alloy in question. The addition of phosphorus increases the Brinell hardness by more than 50 per cent, such improved bearing metals having generally a Brinell hardness of above 30. At the same time however, the addition of phosphorus produces such an improvement in the physical properties of the alloy, that the tendency to crumble (scale) and metals tend to Murmur. AND wILnnLm SANDER, or ESSEN, i 21G METAL ALLOY.

Application filed August 29, .1921. Serial No. 49$,E.

abrasion disappears. Practical experiments have shown that bearing metals high in lead, which have been improved by the introduction of phosphorus, will give the. same technical results as a high-grade white metal alloy containing tin. These new bearing metals may therefore be regarded as fully equivalent substitutes for the latter.

The introduction of phosphorus into the alloy high in lead may be effected directly, but preferablyby using an intermediate alloy. As such, the alloy of phosphoruscopper; phosphorus manganese copper; phosphorus-zinc and phosphorus-brass have been found to be specially suitable. Apart from facilitating the introduction of the phosphorus, the above phosphorus alloys have the advanta e of further improving ing the Brinell hardness, and also ensuring the more reliable working of the bearings.

. Furthermore, we have found that the addition of a very small amount of iron (up to about 1 per cent) considerably diminishes the brittleness of the alloy under consideration increasing at the same time its toughness;

What we claim is:

1. A hearing metal alloy com rising approximately eighty per cent 0 lead, the balance including antimony and tin in amounts not less than ten per cent and five per cent respectively, and approximately 0.5 per cent of phosphorus.

2. A hearing metal alloy consisting mainly of lead, and containing about 10 to 15 per cent of antimony, about 5 to 10 per cent of tin, and about 0.5 per cent of phosphorus.

- 3. A bearingmetal alloy com rising approximately eighty per cent 0 balance including antimony and tin in amounts not less than ten per cent and five per cent respectively, and a small percentage of hosphorus.

n testimony whereof, we have signed our names to this specification in the presence of two subscribing witnesses.

DR. KARL MULLER.

DR. WILHELM SANDER.

Witnesses:

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lead, the 

